Door mounted evacuation systems may be mounted to aircraft doors and covered by a bustle or decorative cover. A gap or clearance between the packed evacuation system and the bustle or decorative cover tends to limit interference with growth of a packed emergency evacuation slide resulting from atmospheric pressure differentials. The gap may provide space for moving parts to work within the door and tends to ensure a smooth, predictable drop of the evacuation slide from the aircraft. The gap or clearance may be within a relatively small range (e.g., 0.5 in to 1 in or 1.3 cm to 2.5 cm) so that measurement of the pack should be accurate. The pack should be in contour at every surface when installed on the aircraft with no part of the pack being out of contour and encroaching on the gap or clearance.
Grid patterned gauges may be used to measure pack sizes. However, grid shaped gauges may have gaps between points on the grid and may leave a substantial percentage of the pack unmeasured. Thus, parts of the pack directly under the grid may be measured while parts of the pack at the openings of the grid may extend out of contour beyond the grid. Furthermore, the gauges may be susceptible to human error when checking contact between a gauge and measuring surface that the gauge registers off. The human error may lead to ambiguity when interpreting contour reading results. In some instances, the gauge may be forced down with excessive force that may damage the packed evacuation slide.